Safety lock for grain elevator man lifts



INVENTOR, FRED E, VAN cg,

A T TO RNE YS Filed April 13, 1949 F E VANCE SAFETY LOCK FOR GRAIN ELEVATOR MAN-LIFTS w M 1 Q. m m F F F.

Patented Feb. 14, 1950 Pnzrnur CE ZSAFE'ITY'LO'CKEFOR onmnnnvnron LIFTS .-.-Ered:E. NaricefSubletteJKams. Application .e rurs, 1949,"Seiiali No." 87:30.4

This invention-relates toea safety'lock fongnain elevator ma-n li'ft.

The *principle-ofagra' elevatorman lifVinvolves a platform, whi'eh=-may be made -ofany material-whichplatform and frame thereof are an "opportunity, by shifting a portion :zof fhis "=1 weight f rom the platform,-- to 'the stationary-veable or rope, to either raise or lower himself and platform as he so desires.

Heretofore, different unsatisfactory means have been employed to retain the platform in a desired stationary condition. These common retaining means have often resulted unsatisfactorily, producing damage and possible serious injury to the operator.

Therefore, an object of this invention is to overcome unsatisfactory results and provide a positive means whereby injury to the platform or to the operator, or both, will be eliminated.

Another object of the invention is to prevent an accident, should the cable suspending the platform be broken, or if the cable should become inoperative for any reason.

With the foregoing and other objects in view, this invention comprises certain novel constructions, combinations, and arrangements of parts as will be hereinafter fully described, illustrated in the accompanying drawings, and more particularly pointed out in the appended claims.

In the drawings:

Figure 1 is a top plan view of a device constructed in accordance with the present invention, while Figure 2 is a view in side elevation.

Figure 3 is an elevated view of the device, partly shown in longitudinal, vertical section and partly in side elevation.

Figure 4 is an enlarged, transverse, sectional view, taken on line 4-4, Fig. 2, and looking in the direction of the arrows.

Referring to the drawings, in which the preferred embodiment of this invention is illustrated, I designates the rail or guide for a manlift. In this rail I, at suitable intervals throughout its height, are placed metal sleeves 2 for the purpose hereinafter described.

l2-iClaims. .(01. 187-92 'Gn the platform 3, which is "provided for =the operator, *is -a primary angle braoket 4; which is suitably eseoured -to said pl atform 3. "A cylinder is monn'ted on *and ox-tends through primary -=brack-et as shown. "h threadetl plug s extends partly into 1 "cylinder v=il sliding bolt .1 extends through threa'ded plug= 8 and the cylinder fi, '-Fig.

3. Within the cylinder 5 is =a coil spring lfl this spring surrounding the sliding bol t Gn'e end of "coil spi ing T presses *against "the threa'ded plug 6 :and "its other end: presses against washer "8; vrasher 8 being mounted on lthe sliding boltfl, and held 1 in position by the :cotter pin 19.- .The

cylinder 5 I is fixe'd against movement .on the 'pr'im aryibracketfl by any ordinary means.

@nplatform 3 are two auxiliary angle brackets j -11) which are arranged in sparallel position and suitably secured in a fixed position upon platform 3 by any ordinary means. Extending through the auxiliary brackets I0 is a primary bolt I I. A flanged wheel I2 is fixedly secured to primary bolt II. A foot pedal I3 is mounted on primary bolt II, between two nut locks I 4. By means of these nut looks the foot pedal I3 is fixedly mounted upon primary bolt II against independent movement upon said bolt. Therefore, when the operator places a foot upon said foot pedal I3 and presses down, the flanged wheel I2 will be rotated clockwise to cause chain I5 to be wound thereon. One end of chain I5 is fastened to the small screw bolt I6 and its opposite end is fastened to pin I! that is attached to the sliding bolt I. When the foot pedal I3 is pressed downwardly, as shown in dotted lines, Fig. 3, the coil spring I will be depressed by reason of the sliding bolt 1 being withdrawn from the metal sleeve 2 in which it may have been extended, whereupon the man-lift is free to move up or down in the elevator shaft, as the case may be.

The flanged wheel l2 has one of its flanges cut away, as at I8. A stop screw bolt l9, Fig. 4, extends through one of the angle brackets Ill. The bolt I9 projects into the path of movement of the flanged wheel 12, working in the cut-away portion I8. When the device is in the position shown in Fig. 2, the stop screw bolt I9 will be engaging the upper end of the cut-away portion I8, as shown. Then when the device is in its releasing position, Fig. 3, the stop screw bolt I9 will be pressing against the lower end of the cutaway portion I8. By this eflicient construction, the inner movement of sliding bolt 1 will be nicely controlled, while when the operator presses downwardly upon the foot pedal I3, unnecessary compression of the coil spring I will be eliminated, since stop screw l9 will be engaging the inner end of the cut-away portion 18, as clearly shown in Fig. 3.

To securely mount stop screw bolt 19 upon the bracket ID, a lock nut 2| is placed on said bolt against one face of the bracket 10. Consequently, the stop screw bolt I9 is efficiently held in its operating position with respect to the flanged wheel I2.

If the man-lift accidentally moves in the elevator shaft, the sliding bolt 1 will enter the first metal sleeve that it registers with, thereby pre-' venting the man-lift from moving any considering bolt extending through said plug and through able distance, and consequently eliminating an accident. The operator can control the movement of the man-lift by manipulating the foot pedal l3. The objects set forth in the first part of the specification further point out the advantages of this invention. I

While I have described the preferred embodiment of my invention and illustrated the same in the accompanying drawings, certain minor changes or alterations may appear to one skilled in the art to which this invention relates during the extensive manufacture of the same, and I, therefore, reserve the right to make such changes oralterations as shall fairly fall within the scope of the appended claims.

What I claim is:

1. In a device of the class described, the combination with a platform, of a pair of angle brackets mounted on said platform, a primary bolt extending through said angle brackets, a flanged wheel fixed to said primary bolt, said flanged wheel having one of its flanges partly cut away, a stop bolt on one of said brackets, said stop bolt extending into said cut-away part said cylinder, a coil spring on said sliding bolt,

said spring within said cylinder, said spring bear- '-ing at its inner end against said threaded plug, a washer on said sliding bolt and pressing against the outer end of said coil spring, a wheel and means mounting said wheel on said platform, flexible means connecting said wheel and said sliding bolt, and a foot pedal connected to said wheel, whereby when said foot pedal is pressed downwardly, said sliding bolt will be drawn inwardly upon said cylinder.

FRED E. VANCE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 776,398 Huffman Nov. 29, 1904 1,068,105 Carman July 22, 1913 1,529,353 Hall Mar. 10, 1925 1,909,697 MacBeth et a1 May 16, 1933 

